THE 



LONDON AND EDINBURGH 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



♦ ■ 



[THIRD SERIES.] 



MARCH 1838. 



XXXI I. On the mutual Voltaic Relations of certain Peroxides^ 

 Platina^ and inactive Iron. By Professor Schgenbein.* 



To Dr. Michael Faraday, 

 My dear Sir, 

 TpROM a series of experiments lately made by me with the 

 -■- view of ascertaining the voltaic relations of some per- 

 oxides, platina, and inactive iron to one another, I have ob- 

 tained results, which, in my opinion, are such as to throw 

 some additional light upon the cause of voltaic electricity, 

 and to modify, to a certain degree at least, the notions we 

 have hitherto entertained about that interesting subject. You 

 will recollect that the voltaic relation of peroxide of lead to 

 iron engaged my attention some time ago f , and you are per- 

 haps also aware of the fact stated by me in PoggendorfF's 

 Annalen, that the peroxide in question, if voltaically associated 

 with iron, disappears by degrees when plunged into nitric acid 

 of any strength. Now as we know that no chemical action 

 whatever takes place under the circumstances mentioned, iron 

 being in its pecuHar condition, and having, in a voltaic point 

 of view, all the properties of platina, I could not but be very 

 much surprised at the disappearance of the peroxide of lead. 

 Although I was not able to trace at the time any voltaic 

 current or to account for any disturbance of the electric equi- 

 librium of the arrangement alluded to, I nevertheless sus- 

 pected that the solution of the substance mentioned was 

 effected under the influence of current electricity. Having 

 now at my disposal a galvanometer which is provided with 

 2000 coils and made in other respects very delicate, I have 

 * Communicated by Dr. Faraday. 



f See Lond. and Edinb. Phil. Mag., vol. x. p. 425. — ^Edit. 

 Phil. Masr, S. 3. Vol. 12. No. 7*. March 1838. 2 B 



